The bankruptcy of VeraSun Energy, a major U.S. ethanol producer, has resulted in the company's liquidation, but the problems haven't ended for its leadership.

An investor in the company, Yaron Gissin, has filed a legal complaint against former executives of the bankrupt firm, claiming they covered up adverse information to buoy VeraSun's stock in violation of securities law.

Gissin is seeking a class-action lawsuit on behalf of himself and other shareholders who lost money on the stock, with the amount of compensation to be determined at trial.

The complaint alleges the VeraSun CEO Donald Endres and vice presidents Danny Herron and Bryan Meier publicly said the company traded in corn futures solely to minimize their exposure to price fluctuations.

"Unknown to investors, however, defendants engaged in highly risky commodities transactions and speculated on their view of the future price of corn in hopes of reaping significant financial gain," the complaint said.

Those bets caused VeraSun to overpay for large quantities of corn when prices fell, prompting the company to report a quarterly loss of up to $103 million in September 2008.

The company's stock price fell precipitously after the announcement and VeraSun filed for bankruptcy the following month, the complaint said.

In 2009, the firm finished selling off all its ethanol plants and filed a liquidation plan under which "shareholders will not receive or retain any distribution or other property on account of their shares," according to a filing with the U.S. Securities and Exchange Commission.

VeraSun's executives claim the complaint should be dismissed because they fully disclosed the risks it faced and did not misrepresent the company's corn prices' hedges.

"Ultimately, VeraSun was felled by extremely difficult market conditions, including the credit crisis, that it did not foresee," the executives said in a court document.